Lift-flap mechanism

ABSTRACT

Lift flap mechanism for adjusting a lift flap assigned to an airplane wing by means of a driving system, the lift flap mechanism comprising a main connection mechanism and a secondary connection mechanism in the form of a guide lever disposed in an articulated manner on the lift flap and the flap track, the main connection mechanism having a steering lever arrangement with at least one steering lever which has a first steering lever joint and a second steering lever joint, the at least one steering lever by way of a pendulum coupled to the first steering lever joint being connected with the flap track, and the second steering lever joint being guided such that, by means of a defined angular position of the at least one steering lever, the positions of the main connection joint and of the secondary connection joint are unambiguously determined.

The invention relates to a lift flap mechanism for adjusting lift flapswhich are arranged on an airplane wing and can be extended andretracted.

In this context, lift flaps are flaps on a manned or unmanned airplane,which influence the lift caused by the structure of the airplane. Suchlift flaps may be uplift slats, such as the leading edge slats ortrailing edge flaps of a transport or passenger plane, as well astrimming surfaces, braking surfaces or control surfaces of any type.

Such a lift flap mechanism is known in the case of the Airbus A340airplane model. In this case, flap tracks are provided which arefastened to the airplane wing and each have a roller path which is usedfor a quasi-linear guidance of the lift flap during its adjustment andfor carrying the main load of the flap. For this purpose, rollingcarriages with steel rollers are fastened to the lift flap, each of thecarriages running on a roller path having a rail flange. For adjustingthe angular position of the lift flap as a function of the position ofthe roller carriage, a lever articulation is provided at a distance fromthe roller carriage, which lever articulation, spaced away from theroller carriage, connects with lift flap with one support respectively.The adjustment takes place by means of a rotatory actuating drive whichis connected with the lift flap by way of driving arms.

It is a disadvantage of these lift flap mechanisms that very large loadsare transmitted from the steel rollers to the rail flanges and stressthe latter with respect to bending, so that large thicknesses ofmaterial are required. These have a very unfavorable effect with respectto weight, particularly in the case of very large wing structures.

It is therefore an object of the invention to provide a flap mechanismin the case of the quasi-linear guidance of the lift flaps, by means ofwhich flap mechanism, the weight can be reduced.

This object is achieved by a lift flap mechanism for adjusting a liftflap assigned to an airplane wing by means of a driving system, the liftflap mechanism being disposed on at least one of several flap tracksfastened to the airplane wing, the lift flap mechanism, for carrying theload and for the kinematic guidance of the lift flap, comprising a mainconnection mechanism and a secondary connection mechanism in the form ofa guide lever disposed in an articulated manner on the lift flap and theflap track, which secondary connection mechanism, viewed in the flowdirection, is arranged at a distance from the main connection mechanism,wherein the main connection mechanism has a steering lever arrangementwith at least one steering lever which has a first steering lever jointand a second steering lever joint, the at least one steering lever byway of a pendulum coupled to the first steering lever joint beingconnected with the flap track, and the second steering lever joint beingguided such that, by means of a defined angular position of the at leastone steering lever, the positions of the main connection joint and ofthe secondary connection joint are unambiguously determined.

In the case of the lift flap mechanism according to the invention, forcarrying the load and for the kinematic guidance of the lift flap, amain connection mechanism is provided and a secondary connectionmechanism in the form of a guide lever disposed in an articulated manneron the lift flap and the flap track is provided, which secondaryconnection mechanism, viewed in the flow direction, is arranged at adistance from the main connection mechanism. The main connectionmechanism has a steering lever arrangement with at least one steeringlever which has a first steering lever joint and a second steering leverjoint, the at least one steering lever, by way of a pendulum coupled tothe first steering lever joint being connected with the flap track, andthe second steering lever joint being guided such that, at a definedangular position of the at least one steering lever, the positions ofthe main connection joint and of the secondary connection joint areunambiguously defined. The guidance of the second steering lever jointmay be designed according to different embodiments according to theinvention.

It is an advantage of the lift flap mechanism according to the inventionthat the transmission of main loads by means of rollers can largely beeliminated so that, in comparison to mechanisms of the prior art, thislift flap mechanism results in a reduction of weight.

Another advantage of the invention is the fact that, by means of a fewchanges of the mechanism, a plurality of extension curves of the liftflap can be created.

In the following, the invention will be described by means of theattached figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a longitudinal sectional view of the area of an airplane wingwhich, viewed in the flow direction, is in the rear and has a lift flapand an embodiment of the lift flap mechanism according to the inventionwith a first embodiment of a steering lever arrangement, the lift flapbeing in a retracted position;

FIG. 2 is a longitudinal sectional view of the rear area of the airplanewing according to FIG. 1, the lift flap being in a central or partiallyextended position;

FIG. 3 is a longitudinal sectional view of the rear area of the airplanewing according to FIG. 1, the lift flap being in a completely extendedposition;

FIG. 4 is a cross-sectional view along Line 4-4 of FIG. 2;

FIG. 5 is a perspective representation of the embodiment of FIGS. 1-4;

FIG. 5 a is a perspective representation of the flap mechanism of theinvention according to FIG. 5;

FIG. 5 b is a perspective representation of the embodiment of the flapmechanism of the invention according to FIG. 1 with a second embodimentof the steering lever arrangement, the lift flap being in a retractedposition;

FIG. 6 is a longitudinal sectional view of the area of an airplane wingwhich, viewed in the flow direction, is in the rear and has a lift flapand another embodiment of the lift flap mechanism according to theinvention with a first embodiment of a steering lever arrangement, thelift flap being in a retracted position;

FIG. 7 is a longitudinal sectional view of the rear area of the airplanewing according to FIG. 6 in the case of a central or partially extendedposition of the lift flap;

FIG. 8 is a longitudinal sectional view of the rear area of the airplanewing according to FIG. 6 in the case of a completely extended positionof the lift flap;

FIG. 9 is a cross-sectional view along Line 9-9 of FIG. 7;

FIG. 10 is a perspective representation of the flap mechanism of theinvention according to FIG. 6;

FIG. 11 is a longitudinal sectional view of the area of an airplane wingwhich, viewed in the flow direction, is in the rear and has a lift flapand a third embodiment of the lift flap mechanism according to theinvention, the lift flap being in a retracted position;

FIG. 12 is a longitudinal sectional view of the rear area of theairplane wing according to FIG. 11 in the case of a central or partiallyextended position of the lift flap;

FIG. 13 is a longitudinal sectional view of the rear area of theairplane wing according to FIG. 11 in the case of a completely extendedposition of the lift flap; and

FIG. 14 is a perspective representation of the flap mechanism accordingto FIG. 11.

DETAILED DESCRIPTION OF THE DRAWINGS

In the description of the figures, characteristics carrying out the samefunctions were given the same names and were provided with the samereference numbers in the different figures.

The figures show a part of a wing or wing body 1 of an airplane which,viewed in the flow direction X (FIG. 1), is in the rear and has atrailing edge flap 2 as the example of a lift flap which can be adjustedby means of at least one flap mechanism 4 disposed on a flap track 3.For this purpose, a driving system 6 is also disposed on the flap track3, for applying adjusting forces to the lift flap 2. Furthermore, theflap mechanism 4 according to the invention comprises a main connectionmechanism 8 and a rear connection mechanism 9, the main connectionmechanism 8 being used for carrying the essential weight loads and theair loads acting upon the trailing edge flap 2, and the rear connectionmechanism 9 together with the main connection mechanism 8 being used forthe kinematic guidance of the trailing edge flap 2.

On the airplane wing for which the invention is provided, normallyseveral flap tracks 3 are provided which, viewed in the wing spandirection Y, are arranged side-by-side and which preferably each have aflap mechanism 4 according to the invention. However, at least one flaptrack 3 with the flap mechanism 4 according to the invention is arrangedon an airplane wing. The flap mechanism 4 may also be combined withother flap mechanisms known from the prior art. In a preferred use ofthe invention, at least two flap tracks 3, each having a flap mechanism4 according to the invention, are arranged on an airplane wing. Inanother preferred application of the invention, the carrying and theadjusting of the lift flap may also take place by means of only one flapmechanism according to the invention arranged on a flap track, in whichcase a further carrying of the lift flap can take place by means ofanother flap mechanism according to the state of the art or by means ofa spherical swivel bearing.

In the following, the invention will be described by means of one ofpreferably several flap tracks 3. First, a first embodiment of theinvention illustrated in FIGS. 1 to 5 will be described:

The driving system 6, which is preferably arranged on the area of thelift flap 2 which, viewed in the flow direction or longitudinaldirection X of the wing, is in the front, is constructed according tothe state of the art and may be constructed in different manners. In apreferred embodiment, this driving system 6 is formed of a rotatoryactuating drive 11 with a driving shaft 12, a combination moved by thisdriving shaft 12 which consists of a driving arm 13 and a driving guiderod 15 which are connected with one another by way of a hinge 16. Thedriving guide rod 15 acts by way of a driving joint 17 and a drivingshaft 17 a pertaining to the latter upon a driving fitting 17 a providedon the trailing edge flap 2, which driving fitting 17 a is preferablyarranged on the front area of the lift flap 2. When the actuating drive16 is operated, by way of the driving shaft 12, the driving arm 13 andthe driving guide rod 15 act upon the driving fitting 17 a in order tomove or adjust the trailing edge flap 2.

In the representation of FIGS. 1 to 14, viewed in the flow direction X,the main connection mechanism 7 is arranged in front of the secondaryconnection mechanism 9. In principle, the main connection mechanism 7may also be arranged behind the secondary connection mechanism 9. By wayof a steering lever arrangement 20, the main connection mechanism 7 actsupon a main connection joint 8 with a main connection fitting 8 a on thelift flap 2, which interacts with a main shaft 8 b. In the firstembodiment illustrated in FIGS. 1 to 5 as well as FIGS. 6 to 10, thesteering lever arrangement is formed of two swinging guide rods orsteering levers 20 a, 20 b (FIG. 5). In the case of the first embodimentof the steering lever arrangement 20, the steering levers 20 a, 20 b aresituated laterally of the flap track 3, so that the flap track 3 isarranged between the steering levers 20 a, 20 b. For this purpose, eachpair of steering levers 20 a, 20 b is mutually connected by way of themain shaft 8 b extending between the latter, which main shaft 8 b ispreferably spherically disposed in the main connection fitting 8 a ofthe main connection joint 8. The bearing may also be provided axially.More than two steering levers may also be provided in a steering leverarrangement 20.

As an alternative, the steering lever arrangement 20 in a secondembodiment may also be formed of a steering lever which may be arrangedbetween the flap track 3 or laterally thereof. Generally, at least onesteering lever is provided in a steering lever arrangement 20.

With respect to its design, the steering lever arrangement 20 can alsobe guided by means of one as well as by means of several steering leverson the flap track 20 by a guiding arrangement 18 which is arranged inthe area of the main connection joint (FIGS. 1 to 10), or can beconstructed without guidance on the flap track 3 FIG. 5 b and FIGS.11-14. In the latter construction, when two or more steering levers 20a, 20 b are used, these are connected with one another by way of a bow19 in the area of the main connection joint 8 (FIG. 5 b; FIG. 14), whichbow 19 is spaced away from the flap track 3. The steering levers may beconnected with the bow 19 in one piece or by way of a connection point.

The guiding arrangement 18 has a steering-rod-side guide 18 a and atrack-side guide 18 b and can be used for supporting the steering leverarrangement 20 in the X-direction as well as in the Y-direction. Theconcrete design of the guiding arrangement 18 is provided according tothe state of the art, in which the steering-rod-side guiding device 18 ais preferably constructed as a carriage 18 c with one roller or morerollers 18 d which interacts or interact with a rail 18 e of thetrack-side guide 18 b.

The at least one steering lever of the steering lever arrangement 20 isguided on the side of the flap track 3 by a first steering lever guide21 and a second steering lever steering lever guide 22. The interactionof the first steering lever guide 21 and the second steering lever guide22 has the result that a certain position of the main connection joint 7is connected with a certain angular slope of the at least one steeringlever.

The first steering lever guide 21 has a first steering lever joint 24 towhich a pendulum 25 is connected which is connected with the flap track3. The second steering lever guide 22 has a second steering lever joint26 arranged in the at least one steering lever The joints 24, 26 arearranged in each provided steering lever 20 a, 20 b, that is, in each atleast one steering lever 20 a, 20 b. The first steering lever joint hasa shaft or swing shaft 24 a which, when two or more steering levers areused per steering lever arrangement 20, mutually connects its steeringlevers. The pendulum 25 is disposed in the flap track 3 by means of apendulum joint 28. In this manner, the pendulum 25 connects the flaptrack 3 with the at least one steering lever which is part of thesteering lever arrangement 20, which causes the first steering leverjoint 24 or the shaft 24 a to carry out a circular motion.

The second steering lever guide 22 with the second steering lever joint26 can be implemented in a different manner. In a first embodiment ofthe second steering lever guide 22 illustrated in FIGS. 1 to 5, thesecond steering lever joint 26, viewed in the longitudinal direction ofthe at least one steering lever, is arranged, at a distance from thefirst steering lever joint 24, at the at least one steering lever 20 a,20 b. In this embodiment, the second steering lever joint 26, by meansof a strut 27, which, by way of a shaft 26 a, is disposed in the secondsteering lever joint 26, is coupled with a strut joint 29 arranged onthe flap track 3. In the representation of FIGS. 1 to 5, the secondsteering lever joint 26 is arranged at the end of the steering leverarrangement situated opposite the main connection joint 8. Depending onthe extension curve to be achieved, the strut 27 may also be linked toanother point of the steering lever arrangement, particularly in thefirst steering lever joint 24.

Since, when two or more steering levers per steering arrangement areprovided, the shaft 24 a of the first steering lever joint 24 mutuallyconnects several steering levers and extends between these, an openingor a slot 30 is optionally provided in the flap track 3, the swing shaft24 a extending through this opening or slot 30. The opening is notrequired when the shaft 24 a is situated laterally of the pertainingflap track 3. Furthermore, one or more reinforcing ribs 31, 32 may bearranged on the flap track 3 in order to achieve a design of the flaptrack 3 which is advantageous with respect to the weight or the flux offorce.

In an area on the lift flap 2 which, viewed in the flow direction X, isspaced away from the main connection joint 8, the secondary connectionmechanism 9 is arranged which has a secondary connection joint 42.Viewed in the flow direction X, the main connection joint 8 may bearranged in front of or behind the secondary connection joint 42. As aresult of the interaction between the main connection mechanism 8 andthe secondary connection mechanism 9, a defined position of the drivingjoint 17 unambiguously determines a defined position of the secondaryconnection joint 42.

The secondary connection mechanism 9 comprises a guide lever 40 which,in turn, is disposed in a track-side guiding joint or fixed-point joint41 on the flap track 3, and, on the other side, is disposed in theflap-side secondary joint 42. The secondary connection joint 42preferably has a shaft 42 b which interacts with a secondary connectionfitting 43 a arranged on the lift flap 2. Depending on the embodiment ofthe flap mechanism or the mobility of the lift flap 2 to be achieved,the secondary connection joint 42 may be a spherical or an only axiallymovable joint.

In the figures, the secondary connection mechanism 9 is arranged behindthe main connection mechanism 7, viewed in the flow direction X.According to the invention, these mechanical devices 7, 9 may also bearranged in the reverse sequence with respect to one another.

The method of operation of the flap mechanism 4 according to theinvention, for the embodiment illustrated in FIGS. 1 to 5, will bedescribed in the following by means of FIGS. 1 to 3. FIG. 1 illustratesthe lift flap 2 operated by the flap mechanism 4 in its retractedposition. In order to move the lift flap 2 into an extended position,the driving system 6 is activated which generates the energy for movingthe lift flap into a different position. The spatial orientation of thelift flap in its respective position is determined by the mainconnection mechanism 8 and the secondary connection mechanism 9 which asa result of their design according to the invention, can advantageouslybe adapted such that a quasi-linear movement of the lift flap 2 occurs.However, other forms of movement can also be achieved by means of theflap mechanism 4 according to the invention. By means of the secondaryconnection mechanism 9, the pitch moment of the lift flap 2 iscompensated which occurs as a result of the weight of the lift flap aswell as the external forces acting upon the latter. FIG. 2 shows acentral extending position of the lift flap 2; and the extended positionis illustrated in FIG. 3.

Another or second embodiment of the main connection mechanism 7 is shownin the following by means of FIGS. 6 to 10, the secondary connectionmechanism 9 being as illustrated in FIGS. 1 to 5. The second embodimentof the main connection mechanism 7 has a steering lever arrangement 20with at least one steering lever. FIGS. 6 to 10 show an embodiment ofthe steering lever arrangement 20 with two steering levers 20 a, 20 b,the steering levers 20 a, 20 b being situated on respective oppositesides of the flap track 3. The steering lever shaft 24 a, to which thependulum 25 is linked, therefore extends through an opening 30correspondingly provided in the flap track 3. In contrast to the firstembodiment of the main connection mechanism 7, in the case of the secondembodiment, the second steering lever guide 22 is constructed such thatthe shaft 26 a disposed in the second steering lever joint 26 is guidedin a guiding slot 50, preferably by means of rollers 50 a which isarranged in the flap track 3. This determines the kinematic mobility ofthe end of the steering lever arrangement 20 situated opposite the mainconnection joint 8, or of the at least one steering lever 20 a, 20 b. Inthis manner, as a result of the interaction of the first steering leverguide 21 and the second steering lever guide 22 with the slope orangular position of the steering lever arrangement 20, a defined andunambiguous position of the main connection joint 8 is determined.

The method of operation of the flap mechanism 4 according to theinvention by means of the second embodiment of the main connectionmechanism 7 is provided analogous to the method of operation of thefirst embodiment and is obtained by means of FIGS. 6 to 8, in which thelift flap 2 is illustrated in three different adjusting positions. FIG.6 shows the flap mechanism 4 in a condition in which the lift flap 2 isin a retracted position. FIG. 7 shows the flap mechanism 4 or the liftflap 2 in a central extending position, while FIG. 8 shows the latter inits completely extended position.

According to the invention, the driving system 6 determines the positionof the driving joint 17, but not the spatial orientation of the liftflap 2 as a function of its extending position. As an alternative to thearrangement of the driving system 6 illustrated in the embodiments ofFIGS. 1 to 10, the latter may, however, also act directly onto one orseveral swing steering rods 20 or 20 a, 20 b, so that then the drivingarm 13 and the driving steering rod 15 are provided in a differentdesign or interact with components of the main connection or secondaryconnection mechanism.

The secondary connection mechanism 9 does not have to have a levermechanism as described in FIGS. 1 to 10. It may also be guided in adifferent manner, for example, by means of a rail.

In another embodiment of the invention, which is illustrated in FIGS. 11to 14, the main connection mechanism 7 and the secondary connectionmechanism 9 are mechanically coupled with one another in order to causean unambiguous position of the main connection joint 8 and of thesecondary connection joint 42 in this manner at a certain angularposition or orientation of the steering lever arrangement 20.

In this embodiment, a connection strut 60 is coupled to the secondsteering lever joint 26, which connection strut 60 mechanically couplesthe steering lever arrangement 20 or the at least one steering lever 20a, 20 b with the guide lever 40. For this purpose, a connection joint 63is arranged on the guide lever 40 for the bearing of the steering leverjoint 20 on the guide lever 40. The connection strut 60 may also bedisposed at a different point on the at least one steering lever or onan extension of the latter or on the pendulum 25. The location of thebearing point determines the extending curve of the lift flap so that,as a result of the selection of the bearing point as well as of theratio of dimensions of the lift flap mechanism, a plurality of flapextending curves are obtained.

The position of the connection joint 63 on the guide lever 40 as well asthe position of the second steering lever joint 26 on the at least onesteering lever 20 a, 20 b depends on the effective lengths of the mainconnection mechanism 7 and of the secondary connection mechanism 9 aswell as the adjusting curve of the lift flap 2 to be achieved. Aprojection or a spacing device 65 may in this case also be provided atthe guide lever 40 (see FIGS. 11 to 14), in order to achieve anendeavored lever effect as a function of the angular position of theguide lever 40. For this purpose, such a spacing device may also beprovided on the at least one steering lever 20 a, 20 b.

Also in the embodiment of the main connection and secondary connectionmechanisms according to FIGS. 11 to 14, the second steering lever joint26 is arranged particularly in the same position as the first steeringlever joint 24. This can be implemented in that the shaft 24 a of thefirst steering lever joint 24 is identical with the shaft 26 a of thesecond steering lever joint 26. However, the second steering lever joint26, to which the connection strut 60 is coupled, may generally also bespaced away from the first steering lever joint 24.

The method of operation of the described embodiments is analogous to themethod of operation described by means of the embodiment according FIGS.1 to 5.

1. Lift flap mechanism for adjusting a lift flap assigned to an airplanewing by means of a driving system, the lift flap mechanism beingdisposed on at least one of several flap tracks fastened to the airplanewing, the lift flap mechanism, for carrying the load and for thekinematic guidance of the lift flap, comprising a main connectionmechanism and a secondary connection mechanism in the form of a guidelever disposed in an articulated manner on the lift flap via a secondaryconnection joint and on the flap track, which secondary connectionmechanism, viewed in the flow direction, is arranged at a distance fromthe main connection mechanism, wherein the main connection mechanism hasa steering lever arrangement with at least one steering lever which hasa first steering lever joint, a second steering lever joint and a mainconnection joint, the at least one steering lever by way of a pendulumcoupled to the first steering lever joint being connected with the flaptrack, and the second steering lever joint being guided such that, bymeans of a defined angular position of the at least one steering lever,positions of the main connection joint and of the secondary connectionjoint are unambiguously determined.
 2. Lift flap mechanism for adjustinga lift flap assigned to an airplane wing, according to claim 1, wherein,for guiding the second steering lever joint, a strut is linked to thelatter, which strut is disposed in an articulated manner on the flaptrack.
 3. Lift flap mechanism for adjusting a lift flap assigned to anair plane wing, according to claim 2, wherein the second steering leverjoint is arranged on an end of the steering lever arrangement situatedopposite the main connection joint.
 4. Lift flap mechanism for adjustinga lift flap assigned to an air plane wing, according to claim 2, whereinthe second steering lever joint is arranged in the first steering leverjoint.
 5. Lift flap mechanism for adjusting a lift flap assigned to anair plane wing, according to claim 1, wherein the second steering leverjoint is guided by means of a shaft in a guideway which is arranged onthe flap track.
 6. Lift flap mechanism for adjusting a lift flapassigned to an air plane wing, according to claim 1, wherein, forguiding the second steering lever joint, a connection strut is linked tothe latter, which connection strut is disposed in an articulated manneron the guide lever.
 7. Lift flap mechanism for adjusting a lift flapassigned to an air plane wing, according to claim 1, wherein, forguiding the pendulum, a connection strut is linked to the latter, whichconnection strut is disposed in an articulated manner on the guidelever.
 8. Lift flap mechanism for adjusting a lift flap assigned to anair plane wing, according to-claim 1, wherein the steering leverarrangement has at least two steering levers, each of which beingsituated in each case on opposite sides of the flap track.
 9. Lift flapmechanism for adjusting a lift flap assigned to an air plane wing,according to claim 8, wherein the at least two steering levers in thearea of the main connection joint by way of a guiding arrangement aresupported by means of a steering-rod-side guiding device and atrack-side guiding device on the flap track.
 10. Lift flap mechanism foradjusting a lift flap assigned to an air plane wing, according to claim8, wherein the at least two steering levers in the area of the mainconnection joint are mutually connected by way of a bow.
 11. Lift flapmechanism for adjusting a lift flap assigned to an air plane wing,according claim 8, wherein the pendulum is arranged on the firststeering lever joint between two steering levers.
 12. Lift flapmechanism for adjusting a lift flap assigned to an air plane wing,according to claim 1, wherein the main connection joint is constructedas a spherical bearing.
 13. Arrangement of at least two flap tracks ofan airplane wing, wherein a lift flap mechanism according to claim 1 isarranged on at least one flap track.
 14. Lift flap mechanism foradjusting a lift flap assigned to an airplane wing, according to claim9, wherein the pendulum is arranged on the first steering lever jointbetween two steering levers.
 15. Lift flap mechanism for adjusting alift flap assigned to an airplane wing, according to claim 9, whereinthe at least two steering levers in the area of the main connectionjoint are mutually connected by way of a bow.